Effect of fractionation and treatment on the acute oral toxicity and on the gossypol and gossypurpurin content of cottonseed pigment glands

Abstract

SummaryTwenty‐one preparations from cottonseed pigment glands were tested for their acute oral toxicity in 1,208 fasted rats and for their content of extractable gossypol and gossypurpurin. LD50 studies on six samples of pure gossypol were performed on 167 fasted rats. There was no correlation between the toxicity of the various samples of cottonseed pigment glands and their extractable gossypol or gossypurpurin content. Samples containing very large amounts of extractable gossypol were less toxic than many samples with considerably lower extractable gossypol content.Various fractionation procedures carried out on the same lot of cottonseed pigment glands caused wide alterations in their toxicity, from the extreme of very marked toxicity for the water‐soluble, acetone‐soluble fraction (LD50 ca. 700 mg./kg.) to no detectable toxicity for the acetone‐insoluble residue (LD50<6,000 mg./kg.).There was a decreased toxicity of subsequently prepared pigment glands with increased time of storage of the cottonseed in a silo. Storage of the pigment glands themselves at 7°C. however had little effect on their toxicity even after 26 and 32 months.The procedures causing greatest detoxification of cottonseed pigment glands, given in the order of increasing effectiveness, were: heating in the presence of water < extraction with ethanol < extraction with acetone.In the fasted rat the acute oral toxicity of pure gossypol was less than that of 17 preparations from cottonseed pigment glands having extractable gossypol contents ranging from as little as 24 to as much as 90%.